Hysteroscopic Adhesiolysis

Malcolm G. Munro MD, FRCSC, FACOG
KEY POINTS 
  • Intrauterine adhesions (IUA) most commonly occur following uterine instrumentation performed from two to four weeks following the end of a pregnancy, but they may also be associated with other uterine procedures or, in endemic countries, in association with uterine tuberculosis.
  • There are a number of classification systems but the simple categorization, introduced by Asherman, classifies them into those with cervical occlusion and those with various degrees of IUA severity. 
  • The diagnosis of cervical occlusion can be made hysteroscopically or, in some instances, with transvaginal ultrasound (TVUS), while intrauterine adhesions are best characterized by HSG, sonohysterography (TVUS with fluid or gel contrast) and, especially, hysteroscopy. 
  • Hysteroscopic adhesiolysis should be considered the standard of care for surgical treatment of IUA. There is no longer a place for blind techniques using a dilator or similar instrument.
  • Identification of appropriate patients and the required training of the surgeon are paramount. Evaluation and categorization of the anticipated nature and extent of adhesions requires a combination of appropriate imaging techniques.
  • Hysteroscopic guidance alone is both adequate and appropriate for division of relatively minor degrees of IUA. More advanced categories should be performed with intraoperative imaging techniques.
  • At the present time, there is no convincing evidence that adjuvant methods including stents, barriers, hormonal therapy and intrauterine gels have value in changing relevant clinical outcomes such as fertility, delivery of a viable infant and peripartum morbidity.
  • Evidence does exist supporting the notion that optimal outcomes for surgical treatment of IUA occur in centers with the combination of necessary infrastructure and appropriately trained and experienced surgeons.
INTRODUCTION
 (Adhesiolysis is currently under construction)
The frequency of intrauterine adhesions (IUA) is difficult to determine, but in clinical medicine is relatively uncommon. In most instances, adhesions are preceded by pregnancy, typically complicated by the requirement for intrauterine procedures such as curettage for incomplete abortion for removal of placental remnants. IUA can also occur following hysteroscopic, laparoscopic or laparotomic surgery such as myomectomy where there is trauma to the endometrium itself. While many intrauterine adhesions are probably clinically irrelevant, they may contribute to amenorrhea, light menstrual bleeding, recurrent pregnancy loss and infertility. Unfortunately, there are relatively few comparative studies of any kind to help inform when surgery should or shouldn’t be offered, particularly in the presence of advanced disease. 
PATHOGENESIS
The core concept of the pathogenesis of IUD is damage to the basilar layer of the endometrium. In the majority of recognized instances, pregnancy is an antecedent event but the disorder may also follow uterine surgery for various conditions and, at least where endemic, by uterine tuberculosis. Histologically, the endometrial stroma is largely substituted with fibrous tissue. The functional and basal layers of the endometrium are indistinguishable and the functional layer is typically replaced by an epithelial monolayer unresponsive to hormonal stimulation as well as areas of fibrotic synechiae that stretch across the cavity (7). This reduced response to gonadal steroids is particularly evident when the adhesions are confined to the lower uterine segment (4).
While the true pathogenesis of IUA is unknown, the gravid or recently gravid uterus is the most common predisposing factor. It is known that molecular and morphological changes associated with gestation potentially make the endometrium more susceptible to the traumatic effect of curettage or other intra uterine procedures. It is known that the low levels of estradiol present immediately following pregnancy negatively impact endometrial regeneration. It is also possible that the pathogenesis of IUA may be facilitated by placental remnants that may enhance fibroblastic activity and result in collagen formation before the process of endometrial regeneration has had a chance to occur (7). Clearly, a near critical component of pathogenesis is intrauterine trauma that induces damage to the basilar layer of the endometrium and adjacent myometrium. Such trauma may compromise vascularization with resulting local hypoxia manifesting in endometrial atrophy and fibrosis (8). 
Endometritis may be a factor that contributes to IUA particularly by acting synergistically with endomyometrial trauma to produce IUA (9). Genital tuberculosis impacting the uterus has been demonstrated to be associated, in some instances, with total obliteration of the endometrial cavity and destruction of the endometrium (10).
PRESENTATION
Menstrual Abnormalities
Many of the women reported to have IUA present with abnormal menstruation or amenorrhea. A review describing clinical presentations identified amenorrhea in 37% and light uterine bleeding in 31%(13). Another study reported an even more profound impact with 78% having menstrual abnormalities - 77.9%. In this group 5.5% had normal periods, 64.4% were amenorrheic, and 30.1% had light bleeding(14). As Asherman noted over 70 years ago, when cervical occlusion is present hematometrium and/or hematosalpinx are rarely seen because the endometrium, for reasons that are unclear, becomes unresponsive to estrogenic stimulation. 
Subfertility/Infertility
Intrauterine adhesions may cause infertility by preventing the ascent of sperm by obstructing the tubal ostia, the endometrial cavity or the cervical canal. A second contributor to infertility or subfertility is the status of the endometrium itself and grossly at least manifest in a thinner than normal morphology. There is a correlation between a thin endometrium and IUA (15). Available evidence suggests that the probability of conceiving with thin endometrial echo complex (EEC) <7 mm is reduced, but the data are mixed as there may be a spectrum of causes of this type of sonographic finding(16).
Recurrent Pregnancy Loss
The association between IUA and recurrent pregnancy loss (RPL) has not been well characterized because it is not clear whether or not adhesions are the cause or result of the adverse event (17). There are at least three factors that may be associated with IUA and RPL, however, it should be emphasized that these are postulates, not established mechanisms(18).
  1. Adhesion induced constriction of the endometrial cavity. 
  2. Inadequate endometrial function. 
  3. Defective endomyometrial vascularization.
DIAGNOSIS
Hysterosalpingography (HSG)
Hysterosalpingography (HSG) has generally been the first line method of investigation for women suspected to have IUA. Provided the cervix is not occluded, filling defects are outlined and there can be simultaneous assessment of tubal patency(19). In addition to issues related to the use of ionizing radiation, the major limitation of HSG is in the context of complete occlusion of the cervcal canal or lower endometrial cavity. Nonetheless it remains a useful tool and may be the major method of diagnosis – at least initially – in many centers. 
Transvaginal Ultrasound (TVUS)
TVUS has limitations as well. An echogenic area may be seen in the EEC or there may be irregular and/or asymmetrical endometrial thickness of the monographically visible endometrium that can suggest the presence of IUA. While there is value in using ultrasound as a component of the evaluation, both the sensitivity and the specificity of TVUS for diagnosing IUA are low: the sensitivity 52% (20) and specificity 11% (21). When HSG or diagnostic hysteroscopy demonstrate cervical canal occlusion, TVUS can identify thin but otherwise normal appearing endometrium above the level of such obstructions and help define the procedure landmarks and required techniques (22). 

There are relatively few available data with which to evaluate the utility of three-dimensional (3D) ultrasound in the detection and characterization of IUA. Using hysteroscopy as a control, HSG and 3D-TVUS were evaluated in a study of 54 women with IUA. While the specificity was only 45%, clinicians using the sonographic technique were able to aid categorization of adhesions better than with HSG. More data regarding this technique, perhaps with intrauterine contrast are needed(23). 
Sonohysterography (SHG)
Sonohysterography (SHG,) is sometimes called saline infusion sonography (SIS) or gell infusion sonography (GIS) depending on the medium infused into the endometrial cavity while the examinaer performs TVUS. Intrauterine adhesions manifest with echogenic areas or bands between the anterior and posterior walls in the liquid-filled endometrial cavity. SHG is highly sensitive and specific and is similar in many ways to hysteroscopy and HSG from a diagnostic perspective(22)(21). Like HSG, the utility is limited when there exists complete occlusion of the cervical canal. 
MRI
The role for MRI in the diagnosis and determination of the extent of IUA is still not clear. The signal characteristics suggesting IUA have not had rigorous evaluation but it is known that T-2 weighted images of normal endometrium have a high signal intensity while the adjacent junctional zone is normally associated with low signal intensity, a circumstance that provides the opportunity for diagnostic utility. For women with IUA, the endometrium may lose its high signal intensity and fibrous bands may show as low signal intensity areas indicating adhesions of the uterine wall(24, 25). 
Hysteroscopy
Endoscopic evaluation of the uterus now the most reliable IUA detection technique. Cervical occlusion can be confirmed, and, if the endometrial cavity can be entered, direct visualization accurately confirms the presence, characteristics and extent of IUA and, to the extent useful can be used to estimate the quality of the endometrium(20, 26) (Figure 21-6 A and B). Properly staged, and preceded by appropriate imaging, hysteroscopy has the advantage of enabling immediate surgical therapy. 
CLASSIFICATION SYSTEMS
To be able to evaluate the extent of the adhesions, determine the most appropriate therapeutic regimen and predict the results of treatment many classifications of the disease have been proposed based on different diagnostic tools. None of these systems are universally accepted or validated, making comparisons between systems difficult. Table 21-2 summarises the various classification systems and Figure 21-2 depicts the system originally adopted by the European Society for Hysteroscopy and used in our studies (11) as well as that of the American Society for Reproductive Medicine, another commonly utilized intrauterine adhesion classification system (12). 
Author Increasing ➤ ➤ Disease ➤ ➤ Severity ➤ ➤
1. Hamou Mild Moderate Severe
Endometrial adhesion are filmy, avascular and easily disrupted Fibromuscular adhesions are characteristically thick but may be covered by endometrium and can bleed when divided Connective tissue adhesions lack any endometrial lining and do not bleed when divided
2. HSG Classification Type 1 Type 2 Type 3 Type 4 Type 5
Atresia of the internal ostium, without concomitant corporal adhesions Stenosis of internal ostium, causing almost complete occlusion without concomitant corporal adhesions Multiple small adhesions in the internal ostium isthmic region Supra isthmic diaphragm causing complete separation of the main cavity from its lower segment Atresia of the internal ostium with concomitant corporeal adhesions
3. March Filmy adhesion occupying less than one-quarter of uterine cavity. Ostial areas and upper fundus minimally involved or clear. One-fourth to three fourth of cavity involved. Ostial areas and upper fundus partially involved. No agglutination of uterine walls More than three fourth of cavity involved. Occlusion of both ostial area and upper fundus. Agglutination of uterine walls
4. Wamsteker/ESGE Type 1 Type 2 Type 2a Type 3 Type 4 Type 5
Thin or fragile adhesions Singular dense adhesions Occluding adhesions only in the region of the internal cervical os. Upper uterine cavity normal. Multiple firm adhesions connecting separate parts of the uterine cavity. Unilateral obliteration of ostial areas of the tubes. � _ Extensive firm adhesions with agglutination of uterine walls. Both tubal ostial areas occluded. With amenorrhea or pronounced hypomenorrhea Complete obliteration of the uterine cavity with amenorrhea
5. American Fertility Society Filmy adhesions in less than one-quarter of uterine cavity involved; thin or filmy adhesions_Ostial areas and upper fundus minimally involved or clear_ Adhesions in one-quarter to three-quarters of uterine cavity involved; ostial areas and upper fundus only partially occluded More than three-quarters of uterine cavity agglutinated; ostial areas and upper cavity occluded
6. Valle and Sciarra Filmy adhesions composed of basal endometrium producing partial or complete uterine cavity occlusion; Fibromuscular adhesions that are characteristically thick, still covered by endometrium that may bleed on division, partially or totally occluding the uterine cavity; Composed of connective tissue with no endometrial lining and likely to bleed upon division, partially or totally occluding the uterine cavity
AFS (ASRM) Classification System Scoring Sheet
In 1988 the ASRM published its classification system for intrauterine adhesions as well as a form that clinicians could use to document the degree of involvement of IUA following appropriate investigation.
SURGEON REQUIREMENTS 
Minor adhesions can be among the most simple hysteroscopic procedures, and can sometimes be divided with the tip of the hysteroscope without any instrumentation or with a simple snip of the scissors. However severe adhesions can be amongst the most challenging hysteroscopic operations with difficult orientation, the requirement for simultaneous imaging and a high risk of perforation. As a result, the prerequisites of surgeon training and skill as well as the ancillary equipment and techniques will vary substantially. The relative novice can divide simple adhesions, but if there is substantial involvement of the endometrial cavity, consultation with an individual with more training and experience is mandatory.
To determine the complexity of the planned operation it is important that patients undergo careful preprocedural evaluation, including some combination of radiological hysterosalpingogram (HSG), transvaginal ultrasound (TVUS), sonohysterography (SHG) and magnetic resonance imaging (MRI). This approach will allow a degree of triage and the assembly of a team and equipment necessary to obtain a safe and optimal clinical outcome.
PROCEDURE LOCATION AND PATIENT PREPARATION
Intrauterine adhesiolysis is a procedure that can be performed in a spectrum of locations with no anesthesia, or using one or some combination of local, regional, intravenous sedation or general anesthetic techniques. Where the procedure is performed and the anesthetic technique(s) used are determined by factors related to the patient, to surgeon training and experience and the location of the equipment and supplies known or anticipated for safe and effective completion of the procedure. The question of antibiotic prophylaxis is frequently asked but evidence is generally lacking making this a decision left to the surgeon. If they are used, short perioperative courses lasting no more than 24 hours are suggested. 
PROCEDURE CONCEPTS
Hysteroscopically-directed adhesiolysis should be performed with a rigid operative hysteroscope and a sheath with an instrument channel that is at least 5 French in diameter. The surgeon should have sharp hysteroscopic scissors; the largest diameter that can easily fit through the instrument channel. It is suggested that transabdominal ultrasound imaging is available, particularly if either cervical canal obstruction is or if extensive intracavitary adhesions are present. It if is anticipated that such imaging is necessary but that ultrasound isn’t available or not likely useful because of body habitus, intraoperative fluoroscopy may be the next choice. The surgeon should avoid performing blind dilation of the cervix for the purpose of accessing endometrial cavity. Such an approach can lead to perforation and may alter the subtle topographical appearance of the cervical canal that provides targeting clues for the dissection planes that must be explored and expanded for optimal restoration of the structure of the endometrial cavity. Consequently, access to the endometrial cavity should be accomplished using the hysteroscope itself. In some instances the exocervix may be stenotic to the point that such access is difficult. In such instances, cruciate incisions and/or careful dilation limited to the exocervix and possibly a centimeter of the lower endocervix is typically adequate to allow the surgeon to position the hysteroscope for direct viewing of the canal.
When the tip of the hysteroscopic system is successfully positioned in the lower cervical canal that is now distended with normal saline, the hysteroscopic scissors or forceps are passed through the instrument channel to dissect and divide adhesions as they are encountered. It is important that the surgeon remains within the boundaries of cervical canal, avoiding dissection into the cervical stroma. Often filmy adhesions are broken down either with pressure of the distending media inflow or by touching them with the tip or sheath of the hysteroscope. 
The endometrial cavity will be entered either directly or after dissection of cervical canal adhesions. Once it is entered, if adhesions are present, adhesiolysis should start centrally before moving to the periphery. During this process the surgeon should be aware of myometrium that, if breached, is typically revealed by bleeding. However, this type of bleeding may be tamponaded if the intrauterine pressure created by the media system in use is too high. As a result, the dissection should proceed using an intrauterine pressure that is the lowest inecessary for acceptable visualization. It is important to avoid the use of energy based devices such as monopolar or bipolar radiofrequency instruments because of the risk of inducing further damage to the already compromized endometrium.
SIMULTANEOUS IMAGE GUIDANCE
Previously we introduced the concept of image guidance when the adhesive disease is known or suspected to be extensive. In our center, where almost all of these procedures are performed under local anesthesia in an office procedure room, the primary choice for image guidance is transabdominal ultrasound, although intraoperative fluoroscopy is an alternative. If such intraoperative imaging is not available, concomitant laparoscopy is an option, however it should be remembered that such guidance may recognize prevention, and, because of the gas used for laoparoscopiy, may limit the risk of bowel injury. There is no evidence that any one method is superior to the other(12-17). 
Intraoperative transabdominal ultrasound is of particular value when there is difficulty accessing to the endometrial cavity because of occlusive cervical canal adhesions. Visualization is aided and enhanced if the bladder is partially filled, a circumstance that creates an accoustic window allowing the tip of the hysteroscope to be seen. With this orientation some combination of sharp and blunt dissection is conducted using hysteroscopic scissors using both the hysteroscopic and the sonographic image to stay within the boundaries of the cervical canal. 
If the endometrial echo complex can be seen it will act as a target for the surgeon as cervical or lower segment dissection is performed. Contrast will be seen to enter the cavity if a passageway is created, a circumstance that will serve as a guide to subsequent dissection. This approach is not feasible for all patients. For example, visualization is often compromised when the patient is obese or when the uterus is severely retroverted and retroflexed. When this circumstance occurs, general anesthesia is often required to allow positioning of a transrectal ultrasound transducer or to facilitate the use of fluoroscopic guidance.
Fluoroscopy typically requires general anesthesia to allow for all of the hysteroscopic and imaging components. The advantage of this approach is that it can help the surgeon identify otherwise occluded pockets that are present behind or above adhesions that are otherwise not visible hysteroscopically (15, 18). This because the contrast medium will find its way through even minor openings in the adhesions. Although ultrasound provides similar information in most patients, and directly images the myometrium, fluoroscopy is somewhat agnostic tot he position of the uterus or the patient’s body habitus. In addition, tubal patency can be assessed during the procedure and the tubes are landmarks of anatomical. Another benefit to intraoperative fluoroscopy is the early detection of a partial or complete uterine perforation. 
Uterine perforation is a known complication of difficult hysteroscopic surgery and may be more often encountered with adhesiolysis of extensive disease. Available evidence suggests that the risk ranges from 0.6 % to 1.5%, in centers with substantial expertise and experience (19)(20). Should perforation occurs either during the introduction of the hysteroscope or with the use of conventional mechanical instruments such as forceps or scissors as they are used under hysteroscopic guidance, there is likely very little risk of intra-abdominal bleeding and intestinal perforation. In such instances expectant management is usually appropriate. 
ADJUVANT MEASURES AND POSTOPERATIVE CARE 
Many centers employ postoperative protocols that includes some combination of an intrauterine device or stent, the use of systemic estrogens and a second look hysteroscopy 4 to 8 weeks postoperatively. Additional dissection is performed at that time if necessary. Intrauterine systems comprise contraceptive devices, special balloon stents, or Foley balloon catheters. Many clinicians also instill anti-adhesive agents, if they are available, that are generally based upon a hyaluronic acid like compound. A retrospective study has demonstrated that an intrauterine balloon combined with an IUD is more effective than the use of hyaluronic acid gel(25). A RCT compared postoperatively use of IUD’s (n=80) and balloons (n=82) and demonstrated that the adhesion reformation rates were similar (balloon, 30%; IUD group, 35%)(26). The role of stem cell therapy is also under investigation (29).
REFERENCES
6. Wamsteker K, Blok SD. Diagnostic hysteroscopy: Technique and documentation. In: Sutton C, Diamond M, editors. Endoscopic Surgery for Gynecologists. Philadelphia, PA: WB Saunders; 1993.
7. The American Fertility Society classifications of adnexal adhesions, distal tubal occlusion, tubal occlusion secondary to tubal ligation, tubal pregnancies, mullerian anomalies and intrauterine adhesions. Fertil Steril. 1988;49(6):944-55. 
8. Schenker JG, Margalioth EJ. Intrauterine adhesions: an updated appraisal. Fertil Steril. 1982;37(5):593-610. 
11. Kasius A, Smit JG, Torrance HL, Eijkemans MJ, Mol BW, Opmeer BC, et al. Endometrial thickness and pregnancy rates after IVF: a systematic review and meta-analysis. Hum Reprod Update. 2014;20(4):530-41. 
12. Soares SR, Barbosa dos Reis MM, Camargos AF. Diagnostic accuracy of sonohysterography, transvaginal sonography, and hysterosalpingography in patients with uterine cavity diseases. Fertil Steril. 2000;73(2):406-11. 
13. Polishuk WZ, Sadovsky E. A syndrome of recurrent intrauterine adhesions. Am J Obstet Gynecol. 1975;123(2):151-8.
14. Wamsteker K. Intrauterine Adhesions (synechiae). In: Brosens IW, K., editor. Diagnostic Imaging and Endoscopy in Gynecology: a practical guide. London: WB Saunders; 1997. p. 171-84. 
15. Salle B, Gaucherand P, de Saint Hilaire P, Rudigoz RC. Transvaginal sonohysterographic evaluation of intrauterine adhesions. J Clin Ultrasound. 1999;27(3):131-4. Paragraph
16. Sylvestre C, Child TJ, Tulandi T, Tan SL. A prospective study to evaluate the efficacy of two- and three-dimensional sonohysterography in women with intrauterine lesions. Fertil Steril. 2003;79(5):1222-5. 
17. Schlaff WD, Hurst BS. Preoperative sonographic measurement of endometrial pattern predicts outcome of surgical repair in patients with severe Asherman's syndrome. Fertil Steril. 1995;63(2):410-3. 
18. Knopman J, Copperman AB. Value of 3D ultrasound in the management of suspected Asherman's syndrome. J Reprod Med. 2007;52(11):1016-22. 
19. Letterie GS, Haggerty MF. Magnetic resonance imaging of intrauterine synechiae. Gynecol Obstet Invest. 1994;37(1):66-8.
20. Bacelar AC, Wilcock D, Powell M, Worthington BS. The value of MRI in the assessment of traumatic intra-uterine adhesions (Asherman's syndrome). Clin Radiol. 1995;50(2):80-3. 
21. Goldenberg M, Schiff E, Achiron R, Lipitz S, Mashiach S. Managing residual trophoblastic tissue. Hysteroscopy for directing curettage. J Reprod Med. 1997;42(1):26-8. 
22. Valle RF, Sciarra JJ. Intrauterine adhesions: hysteroscopic diagnosis, classification, treatment, and reproductive outcome. Am J Obstet Gynecol. 1988;158(6 Pt 1):1459-70. 
23. Pabuccu R, Atay V, Orhon E, Urman B, Ergun A. Hysteroscopic treatment of intrauterine adhesions is safe and effective in the restoration of normal menstruation and fertility. Fertil Steril. 1997;68(6):1141-3. 
24. McComb PF, Wagner BL. Simplified therapy for Asherman's syndrome. Fertil Steril. 1997;68(6):1047-50.
25. Broome JD, Vancaillie TG. Fluoroscopically guided hysteroscopic division of adhesions in severe Asherman syndrome. Obstet Gynecol. 1999;93(6):1041-3. 
26. Deans R, Abbott J. Review of intrauterine adhesions. J Minim Invasive Gynecol. 2010;17(5):555-69. 
27. Hanstede MM, van der Meij E, Goedemans L, Emanuel MH. Results of centralized Asherman surgery, 2003-2013. Fertil Steril. 2015;104(6):1561-8 e1. 
28. Jansen FW, Vredevoogd CB, van Ulzen K, Hermans J, Trimbos JB, Trimbos-Kemper TC. Complications of hysteroscopy: a prospective, multicenter study. Obstet Gynecol. 2000;96(2):266-70. 
29. Hulka JF, Peterson HA, Phillips JM, Surrey MW. Operative hysteroscopy: American Association of Gynecologic Laparoscopists' 1993 membership survey. J Am Assoc Gynecol Laparosc. 1995;2(2):131-2.
30. Lin X, Wei M, Li TC, Huang Q, Huang D, Zhou F, et al. A comparison of intrauterine balloon, intrauterine contraceptive device and hyaluronic acid gel in the prevention of adhesion reformation following hysteroscopic surgery for Asherman syndrome: a cohort study. Eur J Obstet Gynecol Reprod Biol. 2013;170(2):512-6. 
31. Lin XN, Zhou F, Wei ML, Yang Y, Li Y, Li TC, et al. Randomized, controlled trial comparing the efficacy of intrauterine balloon and intrauterine contraceptive device in the prevention of adhesion reformation after hysteroscopic adhesiolysis. Fertil Steril. 2015;104(1):235-40. 
32. Cervello I, Santamaria X, Miyazaki K, Maruyama T, Simon C. Cell Therapy and Tissue Engineering from and toward the Uterus. Semin Reprod Med. 2015;33(5):366-72. 
33. Bellingham FR. Intrauterine adhesions: hysteroscopic lysis and adjunctive methods. Aust N Z J Obstet Gynaecol. 1996;36(2):171-4. 
34. Capella-Allouc S, Morsad F, Rongieres-Bertrand C, Taylor S, Fernandez H. Hysteroscopic treatment of severe Asherman's syndrome and subsequent fertility. Hum Reprod. 1999;14(5):1230-3. 
35. Sanfilippo JS, Fitzgerald MR, Badawy SZ, Nussbaum ML, Yussman MA. Asherman's syndrome. A comparison of therapeutic methods. J Reprod Med. 1982;27(6):328-30. Paragraph
36. Orhue AA, Aziken ME, Igbefoh JO. A comparison of two adjunctive treatments for intrauterine adhesions following lysis. Int J Gynaecol Obstet. 2003;82(1):49-56. 
37. Mensitieri M, Ambrosio L, Nicolais L, Bellini D, O'Regan M. Viscoelastic properties modulation of a novel autocrosslinked hyaluronic acid polymer. Journal of Materials Science: Materials in Medicine. 1996;7(11):695-8. 
38. Amer MI, Abd-El-Maeboud KH. Amnion graft following hysteroscopic lysis of intrauterine adhesions. J Obstet Gynaecol Res. 2006;32(6):559-66. 
VIDEO
Video 1 - Simple mechanical transection of single adhesion 
Video 2 - Adhesiolysis technique with scissors
Video 3 - Extensive cervical and intracavitary adhesions with trans abdominal ultrasound